Folding anchor

ABSTRACT

The invention provides an anchor ( 1 ) with four flukes ( 5, 6, 7, 8 ) which may be folded together for storage purposes, the flukes being both hinged together and hinged to a shank ( 2 ) such that the anchor can be deployed from a stowed to an operational state by a single action, the flukes ( 5, 6, 7, 8 ) and shank arranged to lie in a substantially flat position when stowed.

[0001] The present invention relates to an anchor, and preferably, but not exclusively, to a stowable grapnel anchor for smaller vessels.

[0002] For an anchor to engage with the seabed, it normally has to be of a relatively bulky, in a three dimensional sense, to ensure any fluke, that is the blade or point shaped section, engages with the sea bed or river bed and does not simply lie flat on the seabed.

[0003] The space required to store a conventional anchor is not normally problematic on larger vessels, but on smaller craft this can cause problems, not only due to the space required, but by the potential hazard of having a solid anchor attached to a vessel where protruding limbs may snag or impale. The smaller a vessel is, the more acute the problem of finding a safe stowage space. This is particularly a problem with jet skis where there is very limited space and the nature of the vessel precludes any object likely to snag or impale being stowed externally on the vessel.

[0004] According to the present invention there is provided an anchor comprising a plurality of plates linked together by pivot joints, preferably arranged so that the anchor may lie substantially flat when in a stored state.

[0005] The present invention provides an anchor that can be folded for storage, but which can be easily assembled ready for use. Preferably, the anchor comprises a shank including two portions pivoted together and four flukes, two flukes being pivotally connected to respective shank portions, each fluke connected to the shank portions being pivotally connected to each of two other flukes. Employing four flukes optimises the likelihood of the anchor digging into the seabed or riverbed when dragged across it.

[0006] Preferably the two other flukes each comprise two portions hinged together so that, when the anchor is stowed, each folds substantially in hall, so that they can be folded inwards between the shanks, thus minimising stowage space.

[0007] Preferably, the two portions of the bank have sections arranged to be urged together and held in position, in which position the anchor is in an operational state. This provides a way of ensuring that the anchor cannot be unintentionally folded, for example hen the anchor strikes the seabed.

[0008] Advantageously, the two sections of the shank arranged to be urged together comprise corresponding eyelets by which a line, rope, chain or cable is attached to the anchor.

[0009] Preferably, at least one fluke comprises two sections hinged together whereby when in the employed state the two sections are at an angle relative to each other of between 115° and 155°. This provides the fluke with a “plough” type configuration, such that if dragged across mud the shape of the fluke encourages to the fluke to bury itself in the mud. Preferably, the two sectioned are longer than the single section flukes.

[0010] Preferably the anchor comprises four flukes arranged such that when in an operational state the four flukes form a drogue, permitting the anchor to act as a deep-water anchor. The drogue is advantageously vented, allowing the anchor to clear itself when released from the sea or river bed.

[0011] It is advantageous if each pivotal connection comprises a hinge permitting relative movement about one axis only, for this provides the anchor with a rigid structure.

[0012] One embodiment of the present invention will now be described, by way of example only, with reference to the accompanying figures, in which like numerals are used throughout to indicate like parts, and of which:

[0013]FIG. 1 is a perspective view of an anchor in accordance with the present invention in an operational state;

[0014]FIG. 2 is a front elevation of the anchor of FIG. 1;

[0015]FIG. 3 is the front elevation of FIG. 2 with a front fluke removed;

[0016]FIG. 4 is a side elevation of the anchor of FIG. 1;

[0017]FIG. 5 is a side elevation of the anchor of FIG. 1 when in an stowed state; and

[0018]FIG. 6 is a top view of the anchor in the stowed state of FIG. 5.

[0019] Referring to all the figures together, the anchor, indicated generally as 1, comprises a shank consisting of two portions 2 a and 2 b, pivotally connected together by hinge 3.

[0020] The lower end of each shank 2 a, 2 b is connected via a respective hinge 4 a, 4 b to respective flukes 5, 6, the flukes 5 and 6 arranged in an opposed manner to each other. The flukes 5 and 6 are also both hinged to two further flukes 7 and 8 by associated hinges 9, 10, 11 and 12.

[0021] Each of flukes 7 and 8 comprise two portions 7 a, 7 b and 8 a, 8 b respectively, connected together by hinges 13 and 14 respectively.

[0022] When in a stowed state the anchor, as illustrated n FIGS. 5 and 6, is substantially planar, with each fluke 7 and 8 folded essentially in half and sandwiched between shank sections 2 a and 2 b which are in turn sandwiched between flukes 6 and 7. To deploy the anchor, the top portion of the shanks 2 a and 2 b can be urged together, with either a cord being passed through eyelets 15 and 16 and subsequent pulled tight, (possibly by the weight of the anchor being suspended from the cord when thrown overboard) or, alternatively, the upper portions of the shanks may be pressed together and a shackle passed through them, locking them together.

[0023] Regardless of the method selected to deploy the anchor, urging the upper portion of the shanks 2 a and 2 b together causes the anchor to adopt the operational state illustrated in FIGS. 1 to 4, where the bottom portion of the shanks 2 a and 2 b have been forced apart causing the flukes 5,6,7 and 8 to unfold.

[0024] To avoid clogging of the anchor when used on a muddy or sandy sea or river bed, each of the shanks 2 a and 2 b is formed with an aperture 17,18 with flukes 5 and 6 having further apertures 19, 20 therein In addition, a large aperture 21 is formed between the flukes 5, 6, 7 and 8 with an inverted “V”-shaped portion being formed in the centre of the bottom edge of each fluke.

[0025] The anchor may typically be formed from metal plate 3 or 4 millimetres in thickness, with aluminium and stainless steel being preferred materials. The choice of aluminum or stainless steal may to some extent depend on application, a lightweight aluminium anchor may be preferable for light craft, such as jet skis, where it is not desirable to carry much weight on board when the anchor is stored.

[0026] The weight of the anchor and shape is such that when the anchor is dragged across the seabed via a line attached to the eyelet 15, 16, the anchor will rest on two adjacent flukes. Fluke 5 and 6 terminate in a less acute tip than flukes 7 and 8, causing flukes 5 and 6 to s the anchor such that flukes 7 or 8 tend to “plough” into the seabed.

[0027] In addition to anchoring a vessel to the seabed, the shape of the anchor acts as a drogue in deep water permitting the anchor to act as a drift anchor.

[0028] The above-described embodiment has been given, by way of example only and many alternative designs within the scope of the appended claims will be apparent to those skilled in the art. 

1. An anchor (1) characterised in comprising a plurality of plates (2 a, 2 b, 5, 6, 7 a, 7 b, 8 a, 8 b) linked together by pivot joints (3, 4 a, 4 b, 9, 10, 11, 12).
 2. An anchor as claimed in claim 1, arranged to lie substantially flat when in a stowed state.
 3. An anchor as claimed in claim 1 or 2, comprising a shank including two portions (2 a, 2 b) pivoted together and a plurality of flukes (5, 6, 7, 8), two flukes (5, 6) being pivotally connected to respective shank portions (2 a, 2 b), each fluke connected to the shank portions being pivotally connected to each of two other flukes.
 4. An anchor as claimed in claim 3, wherein the two portions (2 a, 2 b) of the shank have sections arranged to be urged together and held in position, in which position the anchor is arranged to be in an operational state.
 5. An anchor as claimed in claim 4, wherein the two sections of the shank comprise corresponding eyelets (15, 16) by which a line, rope, chain or cable is attached to the anchor.
 6. An anchor as claimed in claim 3, 4 or 5 wherein two other flukes each comprise two sections hinged together such that when the anchor is in a stowed state each is folded substantially in half.
 7. An anchor as claimed in any preceding claim, wherein in a stowed state at least one fluke (7, 8) is sandwiched between the two portions (2 a, 2 b) of the shank.
 8. An anchor as claimed in any preceding claim, wherein at least one fluke (8) comprises two sections (8 a, 8 b) hinged together, whereby when in a operational state the two sections are at an angle relative to each other of between 115° and 155°.
 9. An anchor as claimed in claim 8, comprising two flukes (7, 8), each comprising two sections (7 a, 7 b and 8 a, 8 b) binged together relative to each other, and two flukes (5, 6) each comprising a single sheet, each of the single sheet flukes (5, 6) being hinged to both of the two section flukes (7, 8).
 10. An anchor as claimed in claim 9, wherein the two section flukes (7, 8) are longer than the single sheet flukes (5, 6).
 11. An anchor as claimed in any preceding claim, comprising flukes (5, 6, 7, 8) arranged such that when in an operational state, the four flukes form a drogue.
 12. An anchor as claimed in claim 11, wherein the flukes (5, 6, 7, 8) are arranged such that the drogue is vented.
 13. An anchor as claimed in any preceding claim, wherein at least two of the flukes (5, 6) have apertures (19, 20) therein.
 14. An anchor as claimed in any preceding claim, wherein each pivotal connection comprises a hinge (4 a, 4 b; 9, 10, 11, 12, 13 14) permitting relative movement about one axis only.
 15. An anchor substantially as hereinbefore described with reference to, and/or as illustrated in, one or more of the accompanying figures. 